SAP has just released information about the new features that will be available in BW from release 7.3.
Check out the link below to download a PDF explaining all the new stuff that'll be available:
Features that had me smacking my lips in anticipation included:
Inverse formulas - in your planning layout, if you have a calculated key figure based on two other key figures (e.g. revenue = volume * price), you can allow your users to change the calculated key figure and it works back to change the influencing key figures accordingly.
ABAP-based planning modeler....seems like SAP has listened to the frustrations of all those IP modellers having to configure everything through the portal-based BI Planning Modeller...now the modeller has been moved into SAP GUI